title: A simple machine vision-driven system for measuring optokinetic reflex in small animals.
abstract: The optokinetic reflex (OKR) is useful to monitor the function of the visual and motor nervous systems. However, OKR measurement is not open to all because dedicated commercial equipment or detailed instructions for building in-house equipment is rarely offered. Here we describe the design of an easy-to-install/use yet reliable OKR measuring system including a computer program to visually locate the pupil and a mathematical procedure to estimate the pupil azimuth from the location data. The pupil locating program was created on a low-cost machine vision development platform, whose graphical user interface allows one to compose and operate the program without programming expertise. Our system located mouse pupils at a high success rate (~90 %), estimated their azimuth precisely (~94 %), and detected changes in OKR gain due to the pharmacological modulation of the cerebellar flocculi. The system would promote behavioral assessment in physiology, pharmacology, and genetics.
authors.affiliation: Laboratory for Neural Information Technology, Graduate School of Sciences and Engineering, University of Toyama, 3190 Gofuku, Toyama, Toyama 930-8555, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Shirai
authors.forename: Kenta
authors.initials: K
authors.lastname: Asano
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Takegoshi
authors.forename: Shu
authors.initials: S
authors.lastname: Uchiyama
authors.forename: Yuki
authors.initials: Y
authors.lastname: Nonobe
authors.forename: Toshihide
authors.initials: T
authors.lastname: Tabata
mesh_terms: D000818:Animals; D051379:Mice; D009046:Motor Neurons / Q000502:physiology*; D009424:Nervous System Physiological Phenomena; D011680:Pupil / Q000502:physiology*; D012018:Reflex / Q000502:physiology*; D014785:Vision, Ocular / Q000502:physiology*